Air-conditioning system, controller for air-conditioning apparatus, and control method for air-conditioning apparatus

ABSTRACT

An air-conditioning system includes an air-conditioning apparatus including indoor units, temperature detectors each of which detects a temperature of an associated one of zones into which an air-conditioning target space is divided in association with positions of the indoor units, a human detection sensor which detects whether each of the zones is a human presence zone where a person or persons are present or a human absence zone where no person is present, and a controller that causes the indoor unit in the human presence zone to perform cooling/heating operation, thereby causing a temperature detected by the temperature detector in the human presence zone to reach a set temperature. The controller causes the indoor unit in the human absence zone to perform air-sending operation, and determines the volume of air from the indoor unit in the human absence zone based on that in the human presence zone.

TECHNICAL FIELD

The present disclosure relates to an air-conditioning system thatconditions air in an air-conditioning target space, a controller for anair-conditioning apparatus, and a control method for theair-conditioning apparatus.

BACKGROUND ART

In the past, air-conditioning apparatuses that condition air in a largespace where a lot of persons are present, such as an office building ora business office, have been known (see, for example, Patent Literature1). An air-conditioning apparatus disclosed in Patent Literature 1divides an air-conditioning target space into a plurality of controlregions, classifies the plurality of control regions into a humanpresence control region where a person or persons are present and ahuman absence control region where no person is present, and controlsthe flow rate of refrigerant that flows in each of indoor unitsassociated with the respective control regions. As a specific example,Patent Literature 1 describes that in the case of performing coolingoperation, the air-conditioning apparatus sets a target indoortemperature for the human absence control region to a higher value thanthat for the human presence control region.

CITATION LIST Patent Literature

Patent Literature 1: Japanese Unexamined Patent Application PublicationNo. Hei 11-311437

SUMMARY OF INVENTION Technical Problem

When the number of persons in the human presence control region or theamount of activity of a person in the human presence control regionincreases, an environmental load in the human presence control regionincreases. In this case, for example, the air-conditioning apparatusdisclosed in Patent Literature 1 can be considered to increase thevolume of air from an indoor unit in the human presence control regionto increase the cooling capacity of the indoor unit, while keeping thecooling capacity of an indoor unit in the human absence control regionat a reduced level. As a result, the amount of air convection betweenthe human presence control region and the human absence control regionincreases, and air conditioning in the human absence control region isindirectly performed. Inevitably, the energy consumption of theair-conditioning apparatus increases.

The present disclosure is applied to solve the above problem, andrelates to an air-conditioning system, a controller for anair-conditioning-apparatus, and a control method for theair-conditioning apparatus, which can reduce the energy consumption ofthe air-conditioning apparatus.

Solution to Problem

An air-conditioning system according to an embodiment of the presentdisclosure includes: an air-conditioning apparatus including a pluralityof indoor units each configured to condition air in an air-conditioningtarget space; a plurality of temperature detectors each configured todetect a temperature of an associated one of a plurality of zones intowhich the air-conditioning target space is divided in association withpositions of the plurality of indoor units; a human detection sensorconfigured to detect whether each of the plurality of zones is a humanpresence zone where a person or persons are present or a human absencezone where no person is present; and a controller configured to cause,in the human presence zone detected by the human detection sensor, theindoor unit in the detected human presence zone to perform coolingoperation or heating operation, thereby causing a temperature detectedby an associated one of the temperature detectors to reach a settemperature. The controller is configured to cause the indoor unit inthe human absence zone detected by the human detection sensor to performair-sending operation, and determine a volume of air from the indoorunit in the detected human absence zone based on a volume of air fromthe indoor unit in the human presence zone.

A controller for an air-conditioning apparatus, according to anotherembodiment of the present disclosure, is connected to theair-conditioning apparatus, a plurality of temperature detectors, and ahuman detection sensor. The air-conditioning apparatus includes aplurality of indoor units each configured to condition air in anair-conditioning target space. The plurality of temperature detectorsare configured to detect a temperature of an associated one of aplurality of zones into which the air-conditioning target space isdivided in association with positions of the plurality of indoor units.The human detection sensor is configured to detect whether a person orpersons are present or no person is present in each of the plurality ofzones or not. The controller is configured to: cause the indoor unit inone of the plurality of zones that is detected by the human detectionsensor as a human presence zone where a person or persons are present toperform cooling operation or heating operation, thereby causing atemperature detected by the temperature detector in the human presencezone to reach a set temperature; and cause the indoor unit in one of theplurality of zones that is detected by the human detection sensor as ahuman absence zone where no person is present to perform air-sendingoperation, and determine a volume of air from the indoor unit in thehuman absence zone based on a volume of air from the indoor unit in thehuman presence zone.

A control method for an air-conditioning apparatus, according to stillanother embodiment of the present disclosure, is a method ofcontrolling, using a controller, the air-conditioning apparatus. The airconditioning apparatus includes a plurality of indoor units eachconfigured to condition air in an air-conditioning target space. Thecontroller is connected to the air-conditioning apparatus, a pluralityof temperature detectors, and a human detection sensor. The plurality oftemperature detectors are each configured to detect a temperature of anassociated one of a plurality of zones into which the air-conditioningtarget space is divided in association with positions of the pluralityof indoor units. The human detection sensor is configured to detectwhether a person or persons are present or no person is present in eachof the plurality of zones. The control method includes: causing theindoor unit in one of the plurality of zones that is detected by thehuman detection sensor as a human presence zone where a person orpersons are present to perform cooling operation or heating operation,thereby causing a temperature detected by the temperature detector inthe detected human presence zone to reach a set temperature; and causingthe indoor unit in one of the plurality of zones that is detected by thehuman detection sensor as a human absence zone where no person ispresent to perform air-sending operation, and determining a volume ofair from the indoor unit in the detected human absence zone based on avolume of air from the indoor unit in the human presence zone.

Advantageous Effects of Invention

According to the embodiments of the present disclosure, the coolingoperation or the heating operation is performed in the human presencezone, the air-sending operation is performed in the human absence zone,and the volume of air for the air-sending operation in the human absencezone is determined based on the volume of air for the cooling operationor the heating operation in the human presence zone. This reducesoccurrence of air convection between the human presence zone and thehuman absence zone, thus reducing occurrence of indirect airconditioning in the human absence zone. As a result, the efficiency ofair conditioning in the human presence zone is improved, thus reducingthe energy consumption of the air-conditioning apparatus.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram illustrating a configuration example of anair-conditioning system according to Embodiment 1.

FIG. 2 is a schematic external view of a configuration example of anindoor unit as illustrated in FIG. 1 .

FIG. 3 is an enlarged schematic external view of an airflow directionlouver as illustrated in FIG. 2 .

FIG. 4 is a schematic plan view of an example of the arrangement ofindoor units as illustrated in FIG. 1 in Embodiment 1.

FIG. 5 is a functional block diagram illustrating a configurationexample of a controller in FIG. 1 .

FIG. 6 is a hardware configuration diagram illustrating a configurationexample of the controller as illustrated in FIG. 5 .

FIG. 7 is a hardware configuration diagram illustrating anotherconfiguration example of the controller as illustrated in FIG. 5 .

FIG. 8 is a flowchart of an example of an operation procedure of theair-conditioning system according to Embodiment 1.

FIG. 9 is a flowchart of an example of a specific operation procedure ofthe process of step S110 indicated in FIG. 8 in Embodiment 1.

FIG. 10 is a diagram illustrating an example of the volume of air fromeach of four indoor units as illustrated in FIG. 4 in the case where oneof the indoor units performs cooling operation.

FIG. 11 is a schematic diagram illustrating air flows generated by theindoor units installed in two adjacent zones in a room as illustrated inFIG. 4 .

FIG. 12 is a schematic plan view illustrating another example of thearrangement of the indoor units as illustrated in FIG. 1 in Embodiment1.

FIG. 13 is a diagram illustrating an example of control over 12 indoorunits as illustrated in FIG. 12 in the case where four of the indoorunits perform the cooling operation.

FIG. 14 is a diagram illustrating an example of the control which isperformed in the case where the four indoor units as illustrated in FIG.4 have different air volume adjustment functions.

FIG. 15 is a schematic plan view illustrating an example of thearrangement of the indoor units as illustrated in FIG. 1 in Embodiment2.

FIG. 16 is a flowchart indicating an example of a specific operationprocedure of the process of step S110 indicated in FIG. 8 in Embodiment2.

FIG. 17 is a schematic plan view illustrating another example of thearrangement of the indoor units as illustrated in FIG. 1 , in Embodiment2.

DESCRIPTION OF EMBODIMENTS

Embodiments of the present disclosure will be described in detail withreference to the drawings. Regarding the embodiments, various specificsettings will be described by way of example, and those descriptions arenot limiting. In the embodiments according to the present disclosure,communication means one or both of wireless communication and wiredcommunication. In the embodiments, communication may be a communicationmethod in which wireless communication and wired communication aremixed. The communication method may be, for example, a communicationmethod in which wireless communication is performed in a space and wiredcommunication is performed in another space. Furthermore, a first devicemay communicate with a second device by wire, and the second device maycommunicate with the first device wirelessly. In addition, in order thatthe embodiments be more easily understood, arrows indicating three axes(X axis, Y axis, and Z axis) defining directions are added to some ofthe figures of the drawings.

Embodiment 1

A configuration of an air-conditioning system according to Embodiment 1will be described. FIG. 1 is a block diagram illustrating aconfiguration example of the air-conditioning system according toEmbodiment 1. As illustrated in FIG. 1 , an air-conditioning system 1includes an air-conditioning apparatus 3 that conditions air in anair-conditioning target space, and a controller 30 that controls theair-conditioning apparatus 3. The air-conditioning apparatus 3 includesan outdoor unit 10 and a plurality of indoor units 20-1 to 20-n. Itshould be noted that n is an integer greater than or equal to 2 andrepresents the number of indoor units. Each of the indoor units to 20-nconditions the air in the air-conditioning target space depending onwhich of operation modes is set. In each of the operation modes, anassociated one of a cooling operation, a heating operation, adehumidifying operation, an air-sending operation, etc., is performed.Each indoor unit may have a humidifying function or a moisturizingfunction.

The outdoor unit 10 includes a compressor 11, a four-way valve 12, aheat-source-side heat exchanger 13, and an outdoor fan 14. Each of theindoor units 20-1 to 20-n includes a load-side heat exchanger 21, anexpansion valve 22, an indoor fan 23, and a temperature detector 24. Inaddition to the load-side heat exchanger 21, the expansion valve 22, theindoor fan 23, and the temperature detector 24, a human detection sensor25 is provided in the indoor unit 20-2. The compressor 11 and theheat-source-side heat exchanger 13 are connected to the expansion valve22 and the load-side heat exchanger 21 of each of the indoor units byrefrigerant pipes 15, whereby a refrigerant circuit 40 in whichrefrigerant circulates is formed.

The compressor 11 sucks refrigerant, compresses the sucked refrigerant,and then discharges the compressed refrigerant. The compressor 11 is,for example, an inverter compressor whose capacity is variable. Thefour-way valve 12 changes the flow direction of refrigerant that flowsin the refrigerant circuit 40. The expansion valve 22 reduces thepressure of the refrigerant to expand the refrigerant. The expansionvalve 22 is, for example, an electronic expansion valve. Theheat-source-side heat exchanger 13 is a heat exchanger that causes heatexchange to be performed between the refrigerant and outdoor air. Theload-side heat exchanger 21 is a heat exchanger that causes heatexchange to be performed between the refrigerant and the air in theair-conditioning target space. The heat-source-side heat exchanger 13and the load-side heat exchanger 21 are, for example, finned tube heatexchangers. The outdoor fan 14 is, for example, a propeller fan. Theoutdoor fan 14 changes the volume of air depending on an operatingfrequency. The indoor fan 23 is, for example, a cross-flow fan.

The controller 30 is connected to the temperature detector 24 and thehuman detection sensor 25 in each of the indoor units 20-1 to 20-n bysignal lines (not illustrated), but may be wirelessly connected to thesecomponents. The controller 30 is connected to the compressor 11, thefour-way valve 12, and the outdoor fan 14 by signal lines (notillustrated), but may be wirelessly connected to these components. Thecontroller 30 is connected to the expansion valve 22 and the indoor fan23 in each of the indoor units 20-1 to 20-n by signal lines (notillustrated), but may be wirelessly connected to these components.

FIG. 2 is a schematic external view illustrating a configuration exampleof the indoor unit as illustrated in FIG. 1 . Although the followingdescription concerning Embodiment 1 is made with respect to the casewhere the indoor units 20-1 to 20-n are four-way ceiling cassette typeindoor units, the indoor units are not limited to the four-way ceilingcassette type indoor units. FIG. 2 illustrates an external appearance asthe indoor unit 20-2 mounted on a ceiling is viewed from a regionlocated obliquely below the indoor unit 20-2. The appearanceconfiguration of the indoor unit 20-2 will be described with referenceto FIG. 2 . Since the appearance configurations of the other indoorunits are the same as that of the indoor unit 20-2, their descriptionswill be omitted

As illustrated in FIG. 2 , the indoor unit 20-2 has a lower surface 29that has a rectangular shape. The lower surface 29 has four air outlets27 a to 27 d and an air inlet 26. The air inlet 26 is located in acentral portion of the lower surface 29. At the air inlet 26, a latticeframe (not illustrated) is provided. The air outlets 27 a to 27 d arearranged around the air inlet 26 and extend along four sides of the airinlet 26.

At the air outlets 27 a to 27 d, airflow direction louvers 28 a to 28 dare provided to control the flow direction of air. In the configurationexample as illustrated in FIG. 2 , each of the airflow direction louvers28 a to 28 d includes two rectangular flaps. Specifically, at the airoutlet 27 a, the airflow direction louver 28 a is provided; at the airoutlet 27 b, the airflow direction louver 28 b is provided; at the airoutlet 27 c, the airflow direction louver 28 c is provided; and at theair outlet 27 d, the airflow direction louver 28 d is provided.

FIG. 3 is an enlarged schematic external view of the airflow directionlouver as illustrated in FIG. 2 . FIG. 3 is an enlarged view of theairflow direction louver 28 a of the indoor unit 20-2. In FIG. 3 , theangle of each of the two flaps of the airflow direction louver 28 arelative to a reference plane that is parallel to the ceiling isindicated as a depression angle 8. Each of the two flaps of the airflowdirection louver 28 a has a rotary shaft 45. The rotary shaft 45 isconnected to a driving unit (not illustrated). The driving unit (notillustrated) rotates the rotary shaft 45 to adjust the depression angleθ of the airflow direction louver 28 a.

FIG. 4 is a schematic plan view illustrating an example of thearrangement of the indoor units as illustrated in FIG. 1 inEmbodiment 1. In the example illustrated in FIG. 4 , the number n ofindoor units is four. FIG. 4 illustrates the arrangement of the indoorunits 20-1 to 20-4 in a room RM1 that is an air-conditioning targetspace, as viewed downward from a region located above the ceiling of theroom RM1.

The space in the room RM1 is divided into a plurality of zones Z11 toZ23 in association with the positions of the indoor units 20-1 to 20-4.FIG. 4 illustrates the case where the zones Z21 and Z23 are arranged onthe assumption that indoor units are installed in regions in whichactually, no indoor unit is installed at the ceiling. It is assumedherein that the zones Z11 to Z23 each have a square shape as viewed inplan view.

The temperature detectors 24 each detects a temperature of an associatedone of the four zones arranged in association with the positions of theindoor units 20-1 to The temperature detector 24 in each of the indoorunits 20-1 to 20-4 outputs a detection result to the controller 30. Thetemperature detector 24 is, for example, a temperature sensor, such as athermistor.

The human detection sensor 25 detects, with respect to each of theplurality of zones, whether the zone is a human presence zone where aperson or persons are present or a human absence zone where no person ispresent. The human detection sensor 25 is, for example, an infraredsensor. The human detection sensor 25 outputs, as a detection result,infrared image data which is data obtained by scanning theair-conditioning target space with infrared rays, to the controller 30.In the example illustrated in FIG. 1 , the human detection sensor 25 isprovided at the indoor unit 20-2; however, the human detection sensor 25may be provided at a place other than the indoor unit 20-2. In otherwords, regarding the position of the human detection sensor it sufficesthat the human detection sensor 25 is provided at any position as longas the human detection sensor 25 can determine whether a person orpersons are present in the entire air-conditioning target space or not.

FIG. 5 is a functional block diagram illustrating a configurationexample of the controller as illustrated in FIG. 1 . The controller 30is, for example, a microcomputer. The controller 30 is connected to aremote control (not illustrated) with which a user inputs settinginformation on, for example, an operation mode and a set temperature, tothe air-conditioning apparatus 3. The user may input setting informationto the controller 30, using an information processing terminal includinga personal digital assistant (PDA), such as a smartphone or a tablet,and a personal computer. As illustrated in FIG. 5 , the controller 30includes a refrigeration cycle controller 31, a zone determinationmodule 32, an air-volume controller 33, and an airflow directioncontroller 34.

The zone determination module 32 holds a management table that includesinformation on the arrangement of the indoor units 20-1 to 20-4 and thepositions of the zones Z11 to Z23 as indicated in FIG. 4 . Themanagement table stores information on the coordinates of each of thepositions of the indoor units 20-1 to 20-4, information on thearrangement of zones associated with the positions of the indoor units,and zone information indicating whether each of the zones is the humanpresence zone or the human absence zone. For example, assuming that theindoor unit 20-1 is located at a reference position, the managementtable stores data on a distance Ly1 between the indoor unit 20-1 and theindoor unit 20-2 in a direction along the Y-axis indicated in FIG. 4 .The management table stores data on a distance Lx1 between the indoorunit 20-2 and the indoor unit 20-3 in a direction indicated by an Xarrow in FIG. 4 and data on a distance Ly1 between the indoor unit 20-2and the indoor unit 20-4 in the direction indicated by the Y arrow inFIG. 4 . The zone determination module 32 determines, at regularintervals, whether each of the zones is the human presence zone or thehuman absence zone, based on infrared image data from the humandetection sensor 25. When the result of the above determination differsfrom the zone information stored in the management table, the zonedetermination module 32 updates the management table such that the zoneinformation indicates the latest determination result. When themanagement table is updated, the zone determination module 32 transmitsinformation on the updated management table to the refrigeration cyclecontroller 31 and the air-volume controller 33.

When receiving the information on the management table from the zonedetermination module 32, the refrigeration cycle controller 31 controlsoperation of the indoor unit installed in the human presence zone suchthat a temperature detected by the temperature detector 24 located inthe human presence zone falls within a predetermined temperature rangewith reference to the set temperature.

When the temperature detected by the temperature detector 24 in thehuman presence zone is lower than the set temperature, the refrigerationcycle controller 31 controls the four-way valve 12 to cause therefrigerant discharged from the compressor 11 to flow to the load-sideheat exchanger 21 in order that the indoor unit in the human presencezone perform the heating operation. When the temperature detected by thetemperature detector 24 in the human presence zone is higher than theset temperature, the refrigeration cycle controller 31 controls thefour-way valve 12 to cause the refrigerant discharged from thecompressor 11 to flow to the heat-source-side heat exchanger 13 in orderthat the indoor unit in the human presence zone perform the coolingoperation. The operation mode, such as a heating operation mode or acooling operation mode, may be set by the user.

The refrigeration cycle controller 31 sets the state of the expansionvalve 22 of the indoor unit in the human absence zone to a closed state.The refrigeration cycle controller 31 controls an operating frequency ofthe compressor 11, the operating frequency of the outdoor fan 14, and anopening degree of the expansion valve 22 of the indoor unit 20-2 tocause the temperature detected by the temperature detector 24 in thehuman presence zone to fall within the predetermined temperature rangewith reference to the set temperature. The refrigeration cyclecontroller 31 transmits air-volume control information to the air-volumecontroller 33 and the airflow direction controller 34. This air-volumecontrol information includes information on an air volume set by theuser and information indicating that the indoor unit in the humanabsence zone is caused to perform air-sending operation. The air-volumecontroller 33 controls an operating frequency of the indoor fan 23 ofthe indoor unit in the human presence zone on the basis of the airvolume set by the user. In Embodiment 1, the indoor fan 23 included ineach of the indoor units 20-1 to is configured such that the air volumecan be changed in multiple levels, depending on the operating frequency.For example, the air volume levels are four levels, fL1 to fL4. Thelevels satisfy the relationship “fL1<fL2<fL3<fL4”.

The air-volume controller 33 causes the indoor unit in the human absencezone to perform the air-sending operation, and determines, based on thevolume of air from the indoor unit in the human presence zone, thevolume of air from the indoor unit in the human absence zone. Forexample, the air-volume controller 33 causes the volume of air from theindoor unit in the human absence zone to be larger than the volume ofair from the indoor unit in the human presence zone. In the case where aplurality of human presence zones are present, the air-volume controller33 determines the volume of air from the indoor unit in the humanabsence zone on the basis of the volume of air from the indoor unit inone of the human presence zones that is the closest to the human absencezone. The air-volume controller 33 may increase the volume of air fromthe indoor unit in the human absence zone, depending on the distancebetween the indoor unit in the human absence zone and the indoor unit inthe human presence zone.

The airflow direction controller 34 determines the depression angle θ ofthe airflow direction louvers 28 a to 28 d at the air outlets 27 a to 27d of the indoor unit in the human absence zone on the basis of thedepression angle θ of the airflow direction louvers 28 a to 28 d at theair outlets 27 a to 27 d of the indoor unit in the human presence zone.For example, the airflow direction controller 34 sets the depressionangle θ of the airflow direction louvers 28 a to 28 d at the air outlets27 a to 27 d of the indoor unit in the human absence zone to the sameangle as that of the airflow direction louvers 28 a to 28 d at the airoutlets 27 a to 27 d of the indoor unit in the human presence zone. Anexample of hardware of the controller 30 as illustrated in FIG. 5 willbe described. FIG. 6 is a hardware configuration diagram illustrating aconfiguration example of the controller as illustrated in FIG. 5 . Inthe case where the various functions of the controller 30 are fulfilledby hardware, the controller 30 as illustrated in FIG. 5 includes aprocessing circuit 80 as illustrated in FIG. 6 . The processing circuit80 fulfills the functions of the refrigeration cycle controller 31, thezone determination module 32, the air-volume controller 33, and theairflow direction controller 34 which are provided as illustrated inFIG. 5 .

In the case where the functions are fulfilled by hardware, theprocessing circuit 80 is, for example, a single-component circuit, acomposite circuit, a programmed processor, a parallel-programmedprocessor, an application specific integrated circuit (ASIC), afield-programmable gate array (FPGA), or a combination of those circuitsand processors. The functions of the refrigeration cycle controller 31,the zone determination module 32, the air-volume controller 33, and theairflow direction controller 34 may be fulfilled by individualprocessing circuits 80. The functions of the refrigeration cyclecontroller 31, the zone determination module 32, the air-volumecontroller 33, and the airflow direction controller 34 may be fulfilledby a single processing circuit 80. Another example of the hardware ofthe controller 30 as illustrated in FIG. 5 will be described. FIG. 7 isa hardware configuration diagram illustrating another configurationexample of the controller as illustrated in FIG. 5 . In the case wherethe various functions of the controller 30 are fulfilled by software,the controller 30 as illustrated in FIG. 5 includes a processor 81, suchas a central processing unit (CPU), and a memory 82, as illustrated inFIG. 7 . The processor 81 and the memory 82 fulfill the functions of therefrigeration cycle controller 31, the zone determination module 32, theair-volume controller 33, and the airflow direction controller 34. FIG.7 illustrates the processor 81 and the memory 82 which are connected bya bus 83 such that the processor 81 and the memory 82 can communicatewith each other. In the case where the hardware of the controller 30 hasa configuration as illustrated in FIG. 7 , the memory 82 stores themanagement table. Furthermore, the memory 82 stores programs associatedwith flowcharts, which will be described later.

In the case where the functions are fulfilled by software, the functionsof the refrigeration cycle controller 31, the zone determination module32, the air-volume controller 33, and the airflow direction controller34 are fulfilled by software, firmware, or a combination of software andfirmware. The software and firmware are written as programs and arestored in the memory 82. The processor 81 reads the programs stored inthe memory 82 and runs the programs, thus fulfilling the functions.

As the memory 82, a nonvolatile semiconductor memory, such as aread-only memory (ROM), a flash memory, an erasable and programmable ROM(EPROM), or an electrically erasable and programmable ROM (EEPROM), isused. Also, as the memory 82, a volatile semiconductor memory, such as arandom access memory (RAM), may be used. Furthermore, as the memory 82,for example, a removable recording medium, such as a magnetic disk, aflexible disk, an optical disc, a compact disc (CD), a MiniDisc (MD), ora digital versatile disc (DVD), may be used.

Operation of the controller 30 according to Embodiment 1 will bedescribed. FIG. 8 is a flowchart of an example of the operationprocedure of the air-conditioning system according to Embodiment 1. Thecontroller 30 executes processes indicated in FIG. 8 at regularintervals. For convenience of explanation, of the plurality of zones inthe air-conditioning target space, an arbitrary zone in which the indoorunit is installed is denoted by Zij, where i and j are integers greaterthan or equal to 1. Nx is a maximum value of i, and Ny is a maximumvalue of j.

The zone determination module 32 obtains infrared image data from thehuman detection sensor 25 (step S101). The zone determination module 32determines whether or not it is necessary to update the management tableheld by the zone determination module 32 (step S102). For example, whenthe air-conditioning apparatus 3 is started by the user from anoperation-stopped state in which the air-conditioning apparatus 3 is ina stopped state, the zone determination module 32 determines that it isnecessary to update the management table held by the zone determinationmodule 32. Also, in step S102, the zone determination module 32determines whether or not the position of a human presence zonedetermined based on the obtained infrared image data coincides with thatindicated by data stored in the management table held by the zonedetermination module 32. As the result of the above determination, whendetermining that the human presence zone is changed, the zonedetermination module 32 determines that it is necessary to update themanagement table, and the process proceeds to step S103. By contrast,when determining that the human presence zone is not changed, the zonedetermination module 32 determines that it is not necessary to updatethe management table, and the process proceeds to step S111. In stepS103, the refrigeration cycle controller obtains temperature informationfrom the temperature detector 24 in each of the indoor units 20-1 to20-n and stores the obtained information in the management table held bythe zone determination module 32. The zone determination module 32 sets1 as i of the zone Zij and sets 1 as j of the zone Zij (step S104). Acombination of i and j is represented as (i, j). With respect to theroom RM1 as illustrated in FIG. 4 , combinations of (i, j) are (1, 1),(1, 2), (2, 2), and (1, 3).

The zone determination module 32 determines whether or not the zone Zijis the human presence zone, based on the infrared image data from thehuman detection sensor 25 (step S105). In this case, it is assumed thatZij=Z11. The zone determination module 32 transmits the result of thedetermination to the refrigeration cycle controller 31 and theair-volume controller 33. When the zone determination module 32determines that the zone Zij is the human presence zone, therefrigeration cycle controller 31 causes the indoor unit installed inthe zone Zij to perform the cooling operation or the heating operation(step S106). The refrigeration cycle controller 31 controls theair-conditioning apparatus 3 such that the temperature detected by thetemperature detector 24 in the human presence zone approaches the settemperature.

When it is determined in step S105 that the zone Zij is the humanabsence zone, the refrigeration cycle controller 31 closes the expansionvalve 22 of the indoor unit installed in the zone Zij to cause theindoor unit to perform the air-sending operation (step S107). Theair-volume controller 33 causes the indoor fan 23 of the indoor unit inthe zone Zij to operate. The zone determination module 32 determineswhether or not a condition where i=Nx and j=Ny is satisfied (step S108).When determining that the condition where i =Nx and j=Ny is notsatisfied, the zone determination module 32 changes the value of i or jand determines the next zone Zij (step S109), and the process returns tostep S105. When it is determined in step S108 that the condition wherei=Nx and j=Ny is satisfied and the operation modes in all the zones Zijin which the indoor units are installed are determined, the process bythe air-volume controller 33 proceeds to step S110. Where Zhk is anarbitrary human absence zone, in step S110, the air-volume controller 33controls the volume of air from the indoor unit in the human absencezone Zhk on the basis of the volume of air from the indoor unit in thehuman presence zone.

A specific example of the process of step S110 will be described later.

After the process of step S110 by the air-volume controller 33 ends, therefrigeration cycle controller 31 determines whether or not the settemperature for the human presence zone is changed by the user (stepS111). When determining that the set temperature for the human presencezone is changed by the user, the process by the refrigeration cyclecontroller 31 returns to step S103. The refrigeration cycle controller31 changes details of control over the air-conditioning apparatus 3 onthe basis of the changed set temperature. When determining in S111 thatthe set temperature for the human presence zone is not changed, therefrigeration cycle controller 31 ends the process.

The process of step S110 as indicated in FIG. 8 by the air-volumecontroller 33 will be described in detail. FIG. 9 is a flowchart of anexample of a specific operation procedure of the process of step S110 asindicated in FIG. 8 in Embodiment 1.

The zone determination module 32 refers to the management table andcalculates, with respect to the indoor unit in each of the human absencezones Zhk, a distance L between the indoor unit in the human absencezone Zhk and the indoor unit in the human presence zone (step S201). Inthe case where a plurality of human presence zones are present, the zonedetermination module 32 calculates, with respect to the indoor units ineach of the human absence zones Zhk, the distances L between the indoorunit in the human absence zone Zhk and the indoor units in the humanpresence zones. The zone determination module 32 stores, with respect tothe indoor unit in each of the human absence zones Zhk, the calculateddistance L in the management table.

The air-volume controller 33 refers to the management table anddetermines whether or not a plurality of human presence zones arepresent (step S202). When determining that only one human presence zoneis present, the air-volume controller 33 determines whether or not thedistances L between the indoor units in the human absence zones Zhk andthe indoor unit in the human presence zone are equal to each other (stepS203). When determining that the distances L between the indoor units inthe human absence zones Zhk and the indoor unit in the human presencezone are equal to each other, the air-volume controller 33 sets thevolume of air from the indoor unit in each of the human absence zonesZhk to a value greater than the volume of air from the indoor unit inthe human presence zone (step S204). By contrast, when determining thatthe distances L between the indoor units in the human absence zones Zhkand the indoor unit in the human presence zone are not equal to eachother, the air-volume controller 33 sets the volume of air from theindoor unit in each of the human absence zones Zhk to a value that isgreater than the volume of air from the indoor unit in the humanpresence zone and that depends on an associated one of the distances L(step S205).

When determining in step S202 that a plurality of human presence zonesare present, the air-volume controller 33 determines, with respect toeach of the human absence zones Zhk, one of the indoor units in thehuman presence zones that is separated from the indoor unit in the humanabsence zone Zhk by a shortest distance Lmin which is the shortest oneof the distances between the indoor unit in the human absence zone Zhkand the indoor units in the human presence zones (step S206). Also, withrespect to each of the human absence zones Zhk, the air-volumecontroller 33 sets the volume of air from the indoor unit in the humanabsence zone Zhk to a value that is greater than the volume of air fromthe indoor unit separated from the indoor unit in the human absence zoneZhk by the shortest distance Lmin and that depends on the shortestdistance Lmin (step S207). In steps S205 and S207, the air-volumecontroller 33 increases the operating frequency of the indoor fan 23 ofthe indoor unit in each human absence zone Zhk to increase the volume ofair from the indoor unit. As described above, the volume of air from theindoor unit in each of the human absence zones is set based on thepresent volume of air in the cooling operation or the heating operationof the indoor unit in the human presence zone and the distance L betweenthe indoor unit in the human absence zone and the indoor unit in thehuman presence zone.

A specific example of control that is performed by the controller 30according to the flowcharts indicated in FIGS. 8 and 9 will be describedon the assumption that the air-conditioning target space is the room RM1as illustrated in FIG. 4 . It is assumed that, of the zones Z11 to Z23as illustrated in FIG. 4 , the zone Z12 is a human presence zone, andthe zones Z11, Z21, Z22, Z13, and Z23 are human absence zones. Thefollowing description is made with respect to the case where the indoorunit 20-2 in the zone Z12, which is the human presence zone, performsthe cooling operation; however, the indoor unit 20-2 may perform theheating operation.

FIG. 10 is a diagram illustrating an example of the volume of air fromeach of the four indoor units as illustrated in FIG. 4 in the case whereone of the four indoor units performs the cooling operation. InEmbodiment 1, each of the indoor units 20-1 to 20-4 can change thevolume of air to be sent, in four stages; that is, change the level ofthe volume of the air to four air volume levels, fL1 to fL4, asindicated in FIG. 10 . The air volume levels fL1 to fL4 satisfy therelationship “fL1<fL2<fL3<fL4”.

For the room RM1 as illustrated in FIG. 4 , in steps S105 to S107indicated in FIG. 8 , the refrigeration cycle controller 31 causes theindoor unit 20-2 to perform the cooling operation, and the air-volumecontroller 33 causes the indoor units 20-1, 20-3, and 20-4 to performthe air-sending operation. In the process of step S201 indicated in FIG.9 , the zone determination module 32 refers to the management table, andcalculates, with respect to each of the indoor units in the humanabsence zones Zhk, the distance L between the indoor unit in the humanabsence zone Zhk and the indoor unit 20-2 in the zone Z12. Referring toFIG. 4 , combinations of (h, k) are (1, 1), (2, 2), and (1, 3). Thedistance L between the indoor unit 20-1 and the indoor unit 20-2 is thedistance Ly1, the distance L between the indoor unit 20-2 and the indoorunit 20-3 is the distance Lx1, and the distance L between the indoorunit 20-2 and the indoor unit 20-4 is the distance Ly1. In this case,Lx1=Ly1.

Since it is determined in step S202 that only the zone Z12 is the humanpresence zone, in step S203, he air-volume controller 33 determineswhether the distances L between the indoor units in the human absencezones Zhk and the indoor unit in the human presence zone are equal toeach other or not. In the above case, since the distances L between theindoor units in the human absence zones Zhk and the indoor unit in thehuman presence zone are equal to each other, in the process of stepS204, the air-volume controller 33 sets the level of the volume of airfrom the indoor unit in each of the human absence zones Zhk to a levelhigher than that of the volume of air from the indoor unit 20-2 in thehuman presence zone. In the example illustrated in FIG. 10 , because thelevel of the volume of air from the indoor unit 20-2 in the zone Z12 isthe air volume level fL1, the level of the volume of air from each ofthe indoor units in the human absence zones Zhk is set to the air volumelevel fL2, which is higher than the air volume level fL1 for the indoorunit 20-2, by the air-volume controller 33. FIG. 11 is a schematicdiagram illustrating air flows generated by the indoor units installedin two adjacent zones in the room as illustrated in FIG. 4 . Also, FIG.11 is a schematic side view of the space in the zones Z12 and Z22 inFIG. 4 , as viewed in the direction along the Y-axis. As illustrated inFIG. 11 , air blown from the air outlets 27 b and 27 d of the indoorunit 20-2 in the zone Z12, which is the human presence zone, flows inthe space in the zone Z12 and is then sucked into the air inlet 26 ofthe indoor unit 20-2. Air blown from the air outlets 27 b and 27 d ofthe indoor unit 20-3 in the zone Z22, which is the human absence zone,flows in the space in the zone Z22 and is then sucked into the air inlet26 of the indoor unit 20-3. The volume of air from the air outlet 27 bof the indoor unit 20-3 in the zone Z22 is larger than that from the airoutlet 27 d of the indoor unit 20-2 in the zone Z12. This reducesoccurrence of leakage of a cooling air flow in the human presence zonetherefrom into the human absence zone, thus reducing occurrence of airconvection between the human presence zone and the human absence zonethat are adjacent.

Although the above description is made regarding the indoor unit 20-3 inthe zone Z22 as illustrated in FIG. 4 , with reference to FIG. 11 , thesame is true of the indoor units and 20-4 in the other human absencezones. Accordingly, it is also possible to reduce occurrence of theleakage of a cooling air flow in the zone Z12, which is the humanpresence zone, therefrom into the zones Z11, Z22, and Z13, which are thehuman absence zones, in the arrangement illustrated in FIG. 4 . As aresult, the cooling air flows can be trapped in the human presence zone.

Furthermore, it is assumed that the direction of air from the indoorunit 20-2 is a depression angle e12, and the direction of air from theindoor unit 20-3 is a depression angle e22. In the example illustratedin FIG. 11 , the depression angles e12 and e22 satisfy the relationship“e12=e22”. When the relationship “e12=e22” is satisfied, a cooling airflow blown from the air outlet 27 d of the indoor unit 20-2 and an airflow blown from the air outlet 27 b of the indoor unit 20-3 collide witheach other and then flow parallel to each other and toward a floorsurface. Thus, the air flow in the human absence zone forms an aircurtain perpendicular to the floor surface (in the direction along theZ-axis) at the boundary between the human presence zone and the humanabsence zone, thereby reducing occurrence of leakage of the cooling airflow in the human presence zone into the human absence zone.

The airflow direction controller 34 may adjust, depending on theoperation mode of the indoor unit in the human presence zone, thedepression angle θ corresponding to the direction of air from the indoorunit in the human presence zone and the depression angle θ correspondingto the direction of air from the indoor unit in the human absence zone.For example, when the operation mode of the indoor unit 20-2 is theheating operation mode, the airflow direction controller 34 adjusts theairflow direction louvers 28 a to 28 d of the indoor unit 20-2 such thatthe depression angle e12 approaches 90 degrees. That is, the airflowdirection controller 34 controls the indoor unit 20-2 such that warm airis blown vertically downward from the indoor unit 20-2. In this case,the airflow direction controller 34 adjusts the airflow directionlouvers 28 a to 28 d of the indoor unit 20-3 such that the depressionangle e22 also approaches 90 degrees. By contrast, when the operationmode of the indoor unit 20-2 is the cooling operation mode, the airflowdirection controller 34 adjusts the airflow direction louvers 28 a to 28d of the indoor unit 20-2 such that the depression angle e12 approaches0 degrees. That is, the airflow direction controller 34 controls theindoor unit 20-2 such that cooling air is blown horizontally from theindoor unit 20-2. In this case, the airflow direction controller 34adjusts the airflow direction louvers 28 a to 28 d of the indoor unit20-3 such that the depression angle e22 also approaches 0 degrees.Whichever of the heating operation mode and the cooling operation modeis set, an air flow in the human absence zone forms an air curtainperpendicular to the floor surface at the boundary between the humanpresence zone and the human absence zone, thereby reducing occurrence ofleakage of an air flow in the human presence zone therefrom into thehuman absence zone.

The airflow direction controller 34 may determine the depression angle θcorresponding to the direction of air from the indoor unit in the humanabsence zone on the basis of the distance L between the indoor unit inthe human absence zone and one of the indoor units in the human presencezones that is the closest to the indoor unit in the human absence zone.For example, the airflow direction controller 34 determines thedepression angle θ corresponding to the direction of air from the indoorunit in the human absence zone such that the greater the distance L, thesmaller the depression angle θ. As a result, even when the distance L isgreat, an air flow produced by the air-sending operation in the humanabsence zone easily reaches the human presence zone.

Next, as another specific example, it will be described how thecontroller 30 controls the indoor units in a room RM2 as illustrated inFIG. 12 . FIG. 12 is a schematic plan view illustrating another exampleof the arrangement of the indoor units as illustrated in FIG. 1 inEmbodiment 1. In the example illustrated in FIG. 12 , the number n ofindoor units is 12. FIG. 12 illustrates the arrangement of the indoorunits 20-1 to in the room RM2, which is an air-conditioning targetspace, as viewed from a region above a ceiling of the room RM2. Of thezones Z11 to Z34, the zones Z11, Z12, Z23, and Z14 are human presencezones, and the other eight zones are human absence zones.

It is assumed that the zones as illustrated in FIG. 12 each have asquare shape as viewed in plan view. As illustrated in FIG. 12 , Ly1 isthe distance L between the indoor units in the two zones Z11 and Z12that are adjacent to each other in the direction along the Y-axis, andLx1 is the distance L between the indoor units in the two zones Z11 andZ21 that are adjacent to each other in the direction along the X-axis.The distances Lx1 and Ly1 satisfy the relationship “Lx1=Ly1”. In FIG. 12, indication of the distances Lx1 between the other indoor units in thedirection along the X-axis and the distances Ly1 between the otherindoor units in the direction along the Y-axis is omitted.

Furthermore, where Lxy is the distance L between the indoor unit in thezone Z11 and the indoor unit in the zone Z22 located on an extension ofa diagonal line of the zone Z11, that is, located in an obliquedirection from the zone Z11, the distances Lxy, Lx1, and Ly1 satisfy therelationship “Lxy²=Lx1 ²+Ly1 ²”, that is, “Lxy=Lx1×√2=Ly1×√2”.

For the room RM2 as illustrated in FIG. 12 , in steps S105 to S107indicated in FIG. 8 , the refrigeration cycle controller 31 causes theindoor units 20-1, 20-4, 20-8, and 20-10 perform the cooling operation,and the air-volume controller 33 causes the other eight indoor unitsincluding the indoor unit 20-2 to perform the air-sending operation.

In the process of step S201 indicated in FIG. 9 , the zone determinationmodule 32 refers to the management table and calculates, with respect toeach of the indoor units in the human absence zones Zhk, the distance Lbetween the indoor unit in the human absence zone Zhk and the indoorunit in the human presence zone. In the example illustrated in FIG. 12 ,combinations of (h, k) are (2, 1), (3, 1), (2, 2), (3, 2), (1, 3), (3,3), (2, 4), and (3, 4).

Since it is determined in step S202 that a plurality of human presencezones are present, in step S206, the air-volume controller 33 specifies,with respect to each of the human absence zones Zhk, one of the indoorunits in the human presence zones that is separated from the indoor unitin the human absence zone Zhk by a shortest distance Lmin which is theshortest one of the distances L between the indoor units in the humanpresence zones and the indoor unit in the human absence zone. Forexample, it is assumed that the human absence zone Zhk to be controlledis the zone Z21. In this case, it is determined in step S206 that theindoor unit which is separated from the indoor unit in the human absencezone by the shortest distance Lmin is the indoor unit (Lmin=Lx1). In thecase where, as described above, the zone Z21 is the human absence zoneZhk to be controlled, in step S207, the air-volume controller 33 setsthe level of the volume of air from the indoor unit 20-2 to a level thatis higher than that of the volume of air from the indoor unit 20-1 andthat depends on the shortest distance

Lmin. When the level of the volume of air from the indoor unit 20-1 isthe air volume level fL2, the air-volume controller 33 sets the level ofthe volume of air from the indoor unit 20-2 to the air volume level fL3,which is higher by one level than the air volume level fL2, because theshortest distance Lmin=Lx1 is the shortest one of the above distancesbetween the indoor units.

FIG. 13 is a diagram illustrating an example of the control over each ofthe 12 indoor units as illustrated in FIG. 12 in the case where four ofthe indoor units perform the cooling operation. The volume of air fromeach of the indoor units in the human absence zones other than the zoneZ21 will be described. It is assumed that, as indicated in FIG. 13 , thelevel of the volume of air from each of the indoor units 20-1 and is setto the air volume level fL2, and the level of the volume of air fromeach of the indoor units 20-8 and 20-10 is set to the air volume levelfL1. For the zone Z31, the indoor unit in the human presence zone thatis separated from the indoor unit in the zone Z31 by the shortestdistance Lmin is the indoor unit 20-1, and the shortest distanceLmin=2×Lx1. Since the shortest distance Lmin>Lx1, the air-volumecontroller 33 sets the level of the volume of air from the indoor unit20-3 to the air volume level fL4, which is higher by one level than theair volume level fL3 which is set in the case where the shortestdistance Lmin=Lx1.

For the zone Z22, the indoor units in the human presence zones that areseparated from the indoor unit in the zone Z22 by the shortest distanceLmin are the indoor units 20-4 and 20-8, and the shortest distanceLmin=Lx1=Ly1. The level of the volume of air from the indoor unit 20-4is the air volume level fL2, which is higher than the air volume levelfL1 for the indoor unit 20-8. Therefore, the air-volume controller 33sets the level of the volume of air from the indoor unit 20-5 to the airvolume level fL3, which is higher by one level than the air volume levelfL2 for the indoor unit 20-4.

For the zone Z32, the indoor unit in the human presence zone that isseparated from the indoor unit in the zone Z32 by the shortest distanceLmin is the indoor unit 20-8, and the shortest distance Lmin =Lx1×√2.Although the shortest distance Lmin>Lx1, the air-volume controller 33sets the level of the volume of air from the indoor unit 20-6 to the airvolume level fL3 since the level of the volume of air from the indoorunit is the air volume level fL1.

For the zone Z13, the indoor units in the human presence zones that areseparated from the indoor unit in the zone Z13 by the shortest distanceLmin are the indoor units 20-4, 20-8, and 20-10, and the shortestdistance Lmin=Lx1=Ly1. The level of the volume of air from the indoorunit 20-4 is the air volume level fL2, which is higher than the airvolume level fL1 for the indoor units 20-8 and 20-10. Therefore, theair-volume controller 33 sets the level of the volume of air from theindoor unit 20-7 to the air volume level fL3, which is higher by onelevel than the air volume level fL2 for the indoor unit 20-4.

For the zone Z33, the indoor unit in the human presence zone that isseparated from the indoor unit in the zone Z33 by the shortest distanceLmin is the indoor unit 20-8, and the shortest distance Lmin=Lx1. Sincethe shortest distance Lmin=Lx1 and the level of the volume of air fromthe indoor unit 20-8 is the air volume level fL1, the air-volumecontroller 33 sets the level of the volume of air from the indoor unit20-9 to the air volume level fL2, which is higher by one level than theair volume level fL1 for the indoor unit 20-8.

For the zone Z24, the indoor units in the human presence zones that areseparated from the indoor unit in the zone Z24 are the indoor units 20-8and 20-10, and the shortest distance Lmin=Lx1=Ly1. The shortest distanceLmin=Lx1=Ly1, and the level of the volume of air from each of the indoorunits 20-8 and 20-10 is the air volume level fL1. Therefore, theair-volume controller 33 sets the level of the volume of air from theindoor unit 20-11 to the air volume level fL2, which is higher by onelevel than the air volume level fL1 for the indoor units 20-8 and 20-10.

For the zone Z34, the indoor unit in the human presence zone that isseparated from the indoor unit in the zone Z34 by the shortest distanceLmin is the indoor unit 20-8, and the shortest distance Lmin=Lx1×√2.Although the level of the volume of air from the indoor unit 20-8 is theair volume level fL1, the air-volume controller 33 sets the level of thevolume of air from the indoor unit 20-12 to the air volume level fL3since the shortest distance Lmin>Lx1.

For example, in the case where the volume of air from an indoor unit ina human presence zone is the air volume level fL1, the air-volumecontroller 33 sets the level of the volume of air from an indoor unit ina human absence zone adjacent to the above human presence zone to theair volume level fL2. In the case where a human absence zone is locateddiagonally from the human presence zone, the air-volume controller 33sets the level of the volume of air from the indoor unit in the humanabsence zone to the air volume level fL3. In the case where no humanpresence zone is present around or adjacent to the human absence zone,the air-volume controller 33 sets the level of the volume of air fromthe indoor unit in the human absence zone to the air volume level fL4.

The air-volume controller 33 determines the volume of air from theindoor unit in the human absence zone on the basis of the distancebetween the indoor unit in the human absence zone and the indoor unit inthe human presence zone. As described above with reference to FIG. 13 ,in the case where a plurality of human presence zones are present andthe volumes of air from the indoor units in the human presence zones aredifferent from each other, the air-volume controller 33 determines thevolume of air from the indoor unit in the human absence zone on thebasis of the volume of air from the indoor unit in one of the humanpresence zones that is the closest to the human absence zone.

In the air-conditioning system 1, the air-sending operation of an indoorunit in a human absence zone located around a human presence zonereduces the probability that air adjusted in temperature by acooling/heating operation or the heating operation of an indoor unit inthe human presence zone will flow to the space in the human absencezone. It is therefore possible to efficiently air-condition a zone wherea person or persons are present, in a large indoor space. Even if aplurality of human presence zones are present as illustrated in FIG. 12, it is possible to trap air in each of the human presence zones.

Although the above description is made with reference to FIG. 10 ,regarding the case where the indoor units 20-1 to 20-4 have the same airvolume adjustment function, the indoor units 20-1 to 20-4 may havedifferent air volume adjustment functions. FIG. 14 is a diagramillustrating an example of the control which is performed in the casewhere the four indoor units as illustrated in FIG. 4 have different airvolume adjustment functions. The zone Z12 is a human presence zone, andthe zones Z11, Z22, and Z13 are human absence zones.

As illustrated in FIG. 14 , the volume of air from the indoor unit ineach zone can be changed in three stages, that is, it can be changed tothe three air volume levels fL1 to fL3; however, even in the case wherethe air volume levels set for the indoor units in the zones are the sameas each other, the volumes of air from the indoor units in the zones aredifferent from each other. In the example illustrated in FIG. 14 , thelevel of the volume of air in the cooling operation of the indoor unit20-2 in the zone Z12 is the air volume level fL1. In order for theindoor unit 20-1 in the zone Z11 and the indoor unit 20-3 in the zoneZ22 to obtain a larger volume of air than the volume of air from theindoor unit 20-2 in the case where the level of the volume of air fromthe indoor unit 20-2 is the air volume level fL1, it suffices that thelevels of the volumes of air from the indoor unit 20-1 in the zone Z11and the indoor unit 20-3 in the zone Z22 are set to the air volume levelfL2. On the other hand, in order for the indoor unit 20-4 in the zoneZ13 to obtain a larger volume of air than the volume of air from theindoor unit 20-2 in the case where the level of the volume of air fromthe indoor unit 20-2 is the air volume level fL1, the volume of air fromthe indoor unit 20-4 in the zone Z13 may be set at the air volume levelfL1. As described above, even in the case where the indoor units havedifferent air volume adjustment functions, it suffices that theair-volume controller 33 controls the indoor units such that the volumeof air from the indoor unit in the human absence zone is larger than thevolume of air from the indoor unit in the human presence zone.

The indoor units 20-1 to 20-n may have, as an operation mode, aventilation mode in which ventilation operation is performed to causeindoor air to flow out from an indoor space to the outside and causeoutdoor air to flow into the indoor space. For example, in theventilation mode, the air-volume controller 33 switches the state of aventilation opening (not illustrated) located in the indoor unit, from aclosed state to an opened state. During the cooling operation or theheating operation of the indoor unit in a human presence zone, theindoor units in human absence zones located around the human presencezone perform the ventilation operation for a predetermined period oftime at regular intervals. Thus, it is possible to indirectly air outthe human presence zone because of air exchange to let out air in thehuman presence zone and take outdoor air into the human presence zone.As a result, the temperature variation of the air in the human presencezone is smaller than that in the case where the human presence zone isdirectly ventilated, and clean air can thus be provided in in the humanpresence zone.

In the case of directly ventilating the human presence zone, theair-volume controller 33 switches the state of the ventilation opening(not illustrated) in the indoor unit in the human presence zone from theclosed state to the opened state. However, in this case, the air-volumecontroller 33 may stop the rotation of the indoor fans 23 of the indoorunits in the human absence zones. Thus, during cooling of the humanpresence zone, high-temperature outdoor air can be prevented fromflowing into the human absence zones, thus reducing an increase intemperature of the air in the human absence zones. On the other hand,during heating of the human presence zone, low-temperature outdoor aircan be prevented from flowing into the human absence zones, thusreducing a decrease in temperature of the air in the human absencezones. In such a manner, it is possible to reduce an increase or adecrease in temperature of the air in the human absence zones, and thusreduce an increase in air conditioning load in the human presence zoneeven when air flows from the human absence zones into the human presencezone. As a result, it is possible to further improve the effect ofreducing the energy consumption of the air-conditioning apparatus 3.

The air-conditioning system 1 according to Embodiment 1 includes theair-conditioning apparatus 3 including the indoor units 20-1 to 20-n,the temperature detectors 24 each of which detects a temperature of theassociated one of the zones set in association with the positions of theindoor units 20-1 to 20-n, the human detection sensor 25, and thecontroller 30. The human detection sensor 25 detects whether each of thezones is a human presence zone where a person or persons are present ora human absence zone where no person is present. The controller 30causes the indoor unit in a human presence zone detected by the humandetection sensor 25 to perform the cooling operation or the heatingoperation such that a temperature in the human presence zone that isdetected by the temperature detector 24 reaches a set temperature. Thecontroller 30 causes the indoor unit in the human absence zone of thezones that is detected by the human detection sensor 25 to perform theair-sending operation, and determines the volume of air from the indoorunit in the human absence zone based on the volume of air from theindoor unit in the human presence zone.

In Embodiment 1, the cooling operation or the heating operation isperformed in the human presence zone, the air-sending operation isperformed in the human absence zone, and the volume of air for theair-sending operation in the human absence zone is determined based onthe volume of air for the cooling operation or the heating operation inthe human presence zone. The above description concerning the example ofthe control in Embodiment 1 is made with respect to the case where thevolume of air from the indoor unit in the human absence zone is setlarger than that of the indoor unit in the human presence zone. However,it is also conceivable that the volume of air from the indoor unit inthe human absence zone can be equalized to that of the indoor unit inthe human presence zone. By determining the volume of air from theindoor unit in the human absence zone, depending on the volume of airfrom the indoor unit in the human presence zone, it is possible toreduce occurrence of air convection between the human presence zone andthe human absence zone, thus reducing the probability that the humanabsence zone will be indirectly air-conditioned. As a result, the humanpresence zone is more efficiently air-conditioned, and the energyconsumption of the air-conditioning apparatus 3 can be reduced.

In Embodiment 1, the air-volume controller 33 may cause the volume ofair from the indoor unit in the human absence zone to be larger thanthat of the indoor unit in the human presence zone. In this case,occurrence of the leakage of an air flow in the human presence zonetherefrom into the human absence zone is reduced, thus reducingoccurrence of the air convection between the human presence zone and thehuman absence zone that are adjacent to each other. The space in thehuman presence zone is more reliably isolated from the space in thehuman absence zone, whereby air conditioned by heating or cooling can bemore effectively trapped in the human presence zone.

In Embodiment 1, in the case where a plurality of human presence zonesare present, the air-volume controller 33 determines the volume of airfrom the indoor unit in the human absence zone based on the volume ofair from the indoor unit in one of the human presence zones that is theclosest to the human absence zone. This is because the volume of airfrom the indoor unit in the human absence zone that is the closest tothe human presence zone greatly affects an air curtain produced at theboundary between the human presence zone and the human absence zone.

In Embodiment 1, the air-volume controller 33 may cause the volume ofair from the indoor unit in the human absence zone to increase dependingon the distance between the indoor unit in the human absence zone andthe indoor unit in the human presence zone. For example, in the casewhere the zones each have a square shape as viewed in plan view and thelevel of the volume of air from the indoor unit in the human presencezone is the air volume level fL1, the air-volume controller 33 sets thelevel of the volume of air from the indoor unit in a human absence zoneadjacent to the human presence zone to the air volume level fL2. Theair-volume controller 33 sets the level of the volume of air from theindoor unit in a human absence zone located on an extension of adiagonal line of the human presence zone to the air volume level fL3. Byreducing an excess of the volume of air from the indoor unit in thehuman absence zone adjacent to the human presence zone, it is possibleto reduce the flow of the air in the human absence zone into the humanpresence zone. Thus, an air flow in the human absence zone can serve asan air curtain. By setting the volume of air in the air curtain suchthat the greater the distance by which part of the air curtain islocated apart from the human presence zone, the larger the volume of airin the part of the air curtain, it is possible to provide amulti-layered air curtain around the human presence zone.

In Embodiment 1, the airflow direction controller 34 may determine thedepression angle θ of the airflow direction louvers 28 a to 28 d at theair outlets of the indoor unit in the human absence zone on the basis ofthe depression angle θ of the airflow direction louvers 28 a to 28 d atthe air outlets of the indoor unit in the human presence zone adjacentto the human absence zone. For example, the airflow direction controller34 causes the airflow direction louvers 28 a to 28 d at the air outletsof the indoor unit in the human absence zone to have the same depressionangle θ as that of the airflow direction louvers 28 a to 28 d at the airoutlets of the indoor unit in the human presence zone. Anair-conditioned air flow blown from an air outlet of the indoor unit inthe human presence zone and an air flow blown from an air outlet of theindoor unit in the human absence zone collide with each other and flowparallel to each other. As a result, the air flow in the human absencezone forms an air curtain at the boundary between the human presencezone and the human absence zone, thereby reducing occurrence of leakageof the air flow in the human presence zone therefrom into the humanabsence zone.

Embodiment 2

An air-conditioning system according to Embodiment 2 efficientlyincreases the volume of air that is blown from an indoor unit installedin a human absence zone toward a human presence zone. RegardingEmbodiment 2, components that are the same as those described regardingEmbodiment 1 will be denoted by the same reference signs, and theirdetailed descriptions will be omitted. Regarding Embodiment 2, detaileddescriptions of operations similar to operations described regardingEmbodiment 1 will be omitted, and operations different from those inEmbodiment 1 will be described in detail.

The configuration of the air-conditioning system 1 according toEmbodiment 2 will be described with reference to FIGS. 1 to 3, 5, and 15. FIG. 15 is a schematic plan view illustrating an example of thearrangement of the indoor units as illustrated in FIG. 1 in Embodiment2. In the example illustrated in FIG. 15 , the number n of indoor unitsis four. FIG. 15 illustrates the arrangement of the indoor units 20-1 to20-4 in a room RM3, which is an air-conditioning target space, as viewedfrom a region located above a ceiling of the room RM3. It is assumedthat the zones as illustrated in FIG. 15 each have a square shape asviewed in plan view. Of the zones Z11 to Z22, the zone Z12 is a humanpresence zone. The other three zones are human absence zones.

The air-volume controller 33 causes the indoor unit in each of the humanabsence zones to perform the air-sending operation as in Embodiment 1.In

Embodiment 2, the airflow direction controller 34 receives themanagement table, which is updated by the zone determination module 32,from the refrigeration cycle controller 31. The airflow directioncontroller 34 refers to the management table, and closes one or more ofthe air outlets 27 a to 27 d of the indoor unit in the human absencezone that are relatively remote from the indoor unit in the humanpresence zone. For example, for the zone Z11 as illustrated in FIG. 15 ,the airflow direction controller 34 performs a control to set thedepression angle ∂ of each of the airflow direction louvers 28 a, 28 b,and 27 d as illustrated in FIG. 2 in the indoor unit 20-1 to zero toclose the air outlets 27 a, 27 b, and 27 d. As a result, the volume ofair that is blown from the air outlet 27 c, which is closer to the humanpresence zone than the other air outlets, is increased without changingthe operating frequency of the indoor fan 23 of the indoor unit 20-1.

Next, operation of the air-conditioning system 1 according to Embodiment2 will be described. A control in Embodiment 2 is the same as thecontrol indicated in FIG. 8 described regarding Embodiment 1, except forthe details of the process of step S110. Detailed descriptions of theprocesses other than step S110 will be omitted. FIG. 16 is a flowchartindicating an example of a specific operation procedure of the processof step S110 as indicated in FIG. 8 in Embodiment 2.

The zone determination module 32 refers to the management table, andcalculates, with respect to the indoor unit in each of the human absencezones Zhk, the distance L between the indoor unit in the human absencezone and the indoor unit in the human presence zone (step S301). In thecase where a plurality of human presence zones are present, the zonedetermination module 32 calculates, with respect to each of the indoorunits in the human absence zones Zhk, the distance L between the indoorunit in the human absence zone and each of the indoor units in theplurality of human presence zones. The zone determination module 32stores in the management table, the calculated distance L regarding eachof the indoor units in the human absence zones Zhk.

The airflow direction controller 34 refers to the management table, anddetermines whether a plurality of human presence zones are present ornot (step S302). In the case where only one human presence zone ispresent, the process by the airflow direction controller 34 proceeds tostep S304. When determining in step S302 that a plurality of humanpresence zones are present, the airflow direction controller 34determines, with respect to each of the human absence zones Zhk, one ofthe indoor units in the human presence zones that is separated from theindoor unit in the human absence zone Zhk by the shortest distance Lmin,which is the shortest one of the distances L between the indoor units inthe human presence zones and the indoor unit in the human absence zoneZhk (step S303). The airflow direction controller 34 also determines theabove determined indoor unit as the indoor unit in the human presencezone. In step S304, the airflow direction controller 34 closes one ormore of the air outlets of the indoor unit in each human absence zoneZhk that are relatively remote from the indoor unit in the humanpresence zone (step S304).

In the case where the human absence zone Zhk is the zone Z11 in the roomRM3 provided as illustrated in FIG. 15 , the airflow directioncontroller 34 closes the air outlets 27 a, 27 b, and 27 d of the indoorunit 20-1 in step S304 indicated in FIG. 16 . As a result, the volume ofair that is blown from the air outlet 27 c close to the human presencezone is increased without the need for the air-volume controller 33 tochange the operating frequency of the indoor fan 23 of the indoor unit20-1.

In the case where the human absence zone Zhk is the zone Z21 provided asillustrated in FIG. 15 , the airflow direction controller 34 closes theair outlets 27 a and 27 d of the indoor unit 20-2 in step S304 indicatedin FIG. 16 . As a result, the volume of air which is blown from the airoutlets 27 b and 27 c which are close to the human presence zone isincreased without the need for the air-volume controller 33 to changethe operating frequency of the indoor fan 23 of the indoor unit 20-2.

In the case where the human absence zone Zhk is the zone Z22 provided asillustrated in FIG. 15 , the airflow direction controller 34 closes theair outlets 27 a, 27 c, and 27 d of the indoor unit 20-4 in step S304indicated in FIG. 16 . As a result, the volume of air which is blownfrom the air outlet 27 b close to the human presence zone is increasedwithout the need for the air-volume controller 33 to change theoperating frequency of the indoor fan 23 of the indoor unit 20-4.

FIG. 17 is a schematic plan view illustrating another example of thearrangement of the indoor units as illustrated in FIG. 1 in Embodiment2. In the example illustrated in FIG. 17 , the number n of indoor unitsis nine. FIG. 17 illustrates the arrangement of the indoor units 20-1 to20-9 in a room RM 4 which is an air-conditioning target space, as viewedfrom a region located above a ceiling of the room RM4. It is assumedthat the zones as illustrated in FIG. 17 each have a square shape asviewed in plan view. Of the zones Z11 to Z33, the zone Z22 is a humanpresence zone, and the other eight zones are human absence zones.

It will be described how the airflow direction controller 34 controlsthe indoor units in the human absence zones, which are included in theindoor units 20-1 to 20-9 as illustrated in FIG. 17 . With respect toeach of the indoor units 20-1, 20-3, 20-7, and 20-9 in four humanabsence zones located on extensions of diagonal lines of the humanpresence zone, the airflow direction controller 34 closes two of thefour air outlets 27 a to 27 d that are relatively remote from the humanpresence zone. With respect to each of the indoor units 20-2, 20-4,20-6, and 20-8 in four human absence zones which are adjacent to thehuman presence zone, the airflow direction controller 34 closes one ofthe four air outlets 27 a to 27 d that is relatively remote from thehuman presence zone.

In Embodiment 2, as described above with reference to FIGS. 15 and 17 ,occurrence of the leakage of a conditioned air flow in the humanpresence zone therefrom into the human absence zones is reduced, andoccurrence of air convection between the zones is reduced, therebyimproving the efficiency of air conditioning in the human presence zone.

In Embodiment 2, the control as described above regarding Embodiment 1may also be applied. For example, the air-volume controller 33 mayincrease the volume of air from the indoor unit in the human absencezone, depending on the distance between the indoor unit in the humanabsence zone and the indoor unit in the human presence zone. Withrespect to the plurality of zones as illustrated in FIGS. 15 and 17 ,the number of human presence zones is not limited to one. In addition,the number n of indoor units is not limited to four which is that in theexample illustrated in FIG. 15 or nine which is that in the exampleillustrated in FIG. 17 .

In the air-conditioning system 1 according to Embodiment 2, the indoorunit in each of the human absence zones has a plurality of air outlets,and the controller 30 closes one or more of the plurality of air outletsthat are relatively remote from the indoor unit in the human presencezone.

In Embodiment 2, the volume of air that is blown from the indoor unit inthe human absence zone toward the human presence zone can be increasedwithout the need to change the operating frequency of the indoor fan ofthe indoor unit in the human absence zone. It is therefore possible toreduce an increase in the energy consumption that would be caused by anincrease in the operating frequency of the indoor fan, and improve theefficiency of air conditioning in the human presence zone. Thus, theenergy consumption of the air-conditioning apparatus 3 is furtherreduced than in Embodiment 1.

The above descriptions concerning Embodiments 1 and 2 are made withrespect to the case where each of the zones has a square shape as viewedin plan view. The shape of each zone as viewed in plan view is notlimited to the square shape; that is, the zones may each have arectangular shape as viewed in plan view. The shapes of the zones asviewed in plan view may be different from each other. Each of the indoorunits is not limited to a four-way ceiling cassette type indoor unit.For example, each indoor unit may be a two-way ceiling cassette typeindoor unit. An indoor unit which is close to a wall of a room which isan air-conditioning target space may be a wall-mounted indoor unit. Theair-conditioning apparatus 3 may include a plurality of outdoor units10.

REFERENCE SIGNS LIST

1: air-conditioning system, 3: air-conditioning apparatus, 10: outdoorunit, 11: compressor, 12: four-way valve, 13: heat-source-side heatexchanger, 14: outdoor fan, 15: refrigerant pipe, 20-1 to 20-n: indoorunit, 21: load-side heat exchanger, 22:

expansion valve, 23: indoor fan, 24: temperature detector, 25: humandetection sensor, 26: air inlet, 27 a to 27 d: air outlet, 28 a to 28 d:airflow direction louver, 29: lower surface, controller, 31:refrigeration cycle controller, 32: zone determination module, 33:air-volume controller, 34: airflow direction controller, 40: refrigerantcircuit, 45: rotary shaft, 80: processing circuit, 81: processor, 82:memory, 83: bus, RM1 to RM4: room, Z11 to Z34: zone

1. An air-conditioning system comprising: an air-conditioning apparatusincluding a plurality of indoor units each configured to condition airin an air-conditioning target space; a plurality of temperature sensorseach configured to detect a temperature of an associated one of aplurality of zones into which the air-conditioning target space isdivided in association with positions of the plurality of indoor units;a human detection sensor configured to detect whether each of theplurality of zones is a human presence zone where a person or personsare present or a human absence zone where no person is present; and acontroller configured to cause, in the human presence zone detected bythe human detection sensor, the indoor unit in the detected humanpresence zone to perform cooling operation or heating operation, therebycausing a temperature detected by an associated one of the temperaturesensors to reach a set temperature, wherein the controller is configuredto: cause the indoor unit in the human absence zone detected by thehuman detection sensor to perform air-sending operation, and determine avolume of air from the indoor unit in the detected human absence zonebased on a volume of air from the indoor unit in the human presencezone; and cause the volume of air from the indoor unit in the humanabsence zone to be larger than the volume of air from the indoor unit inthe human presence zone.
 2. The air-conditioning system of claim 1,wherein the controller is configured to determine, when a plurality ofthe human presence zones are present, the volume of air from the indoorunit in the human absence zone based on the volume of air from theindoor unit in one of the human presence zones that is the closest tothe human absence zone.
 3. (canceled)
 4. The air-conditioning system ofclaim 1, wherein the human detection sensor includes an infrared sensor.5. A controller for an air-conditioning apparatus, which is connected tothe air-conditioning apparatus, a plurality of temperature sensors, anda human detection sensor, the air-conditioning apparatus including aplurality of indoor units each configured to condition air in anair-conditioning target space, the plurality of temperature sensors eachbeing configured to detect a temperature of an associated one of aplurality of zones into which the air-conditioning target space isdivided in association with positions of the plurality of indoor units,the human detection sensor being configured to detect whether a personor persons are present or no person is present in each of the pluralityof zones or not, wherein the controller is configured to: cause theindoor unit in one of the plurality of zones that is detected by thehuman detection sensor as a human presence zone where a person orpersons are present to perform cooling operation or heating operation,thereby causing a temperature detected by the temperature sensor in thehuman presence zone to reach a set temperature; cause the indoor unit inone of the plurality of zones that is detected by the human detectionsensor as a human absence zone where no person is present to performair-sending operation, and determine a volume of air from the indoorunit in the human absence zone based on a volume of air from the indoorunit in the human presence zone; and cause the volume of air from theindoor unit in the human absence zone to be larger than the volume ofair from the indoor unit in the human presence zone.
 6. The controllerof claim 5, wherein the controller is configured to determine, when aplurality of the human presence zones are present, determine the volumeof air from the indoor unit in the human absence zone based on thevolume of air from the indoor unit in one of the human presence zonesthat is the closest to the human absence zone.
 7. (canceled)
 8. Thecontroller of claim 5, wherein the controller is configured to increasethe volume of air from the indoor unit in the human absence zone,depending on a distance between the indoor unit in the human absencezone and the indoor unit in the human presence zone.
 9. The controllerof claim 5, wherein the indoor unit in the human absence zone has aplurality of air outlets, and the controller is configured to close atleast one of the plurality of air outlets that is relatively remote fromthe indoor unit in the human presence zone.
 10. The controller of claim5, wherein the controller is configured to determine a depression angleof an airflow direction louver at an air outlet of the indoor unit inthe human absence zone, based on a depression angle of an airflowdirection louver at an air outlet of the indoor unit in the humanpresence zone adjacent to the human absence zone.
 11. The controller ofclaim 5, wherein the controller is configured to control an operatingfrequency of each of a compressor and an outdoor fan that are includedin the air-conditioning apparatus to cause a temperature detected by thetemperature sensor in the human presence zone to fall within apredetermined range with reference to the set temperature.
 12. A methodof controlling, using a controller, an air-conditioning apparatusincluding a plurality of indoor units each configured to condition airin an air-conditioning target space, the controller being connected tothe air-conditioning apparatus, a plurality of temperature sensors, anda human detection sensor, the plurality of temperature sensors eachbeing configured to detect a temperature of an associated one of aplurality of zones into which the air-conditioning target space isdivided in association with positions of the plurality of indoor units,the human detection sensor being configured to detect whether a personor persons are present or no person is present in each of the pluralityof zones, the method comprising: causing the indoor unit in one of theplurality of zones that is detected by the human detection sensor as ahuman presence zone where a person or persons are present to performcooling operation or heating operation, thereby causing a temperaturedetected by the temperature sensor in the detected human presence zoneto reach a set temperature; and causing the indoor unit in one of theplurality of zones that is detected by the human detection sensor as ahuman absence zone where no person is present to perform air-sendingoperation, and determining a volume of air from the indoor unit in thedetected human absence zone based on a volume of air from the indoorunit in the human presence zone, wherein in the determining the volumeof air from the indoor unit in the human absence zone based on thevolume of air from the indoor unit in the human presence zone, thevolume of air from the indoor unit in the human absence zone is causedto be larger than the volume of air from the indoor unit in the humanpresence zone.